Intraocular lenses (IOLs) may be used within the eye for restoring vision function, for example, via implant for patients of cataract surgery. IOLs include monofocal lenses, which provide a single focal point or single optical power, multifocal lenses, which provide multiple focal points or optical powers, and accommodating lenses, which adjust the focus focal point or optical power of a lens.
The IOL may be inserted in a folded state through a small 3 mm or less incision of the eye. A syringe-like device having a piston may be used to help apply and position the IOL into the capsular bag which previously housed the removed natural crystalline lens. Once in the eye, the IOL may be unfolded to its natural state. When the incision size for inserting an IOL into the eye is larger than 2-3 mm undesired astigmatic changes of the cornea occur. Therefore ophthalmologists prefer to use the smallest incision possible for inserting an IOL into the eye. Therefore this makes a flexible and foldable IOL practically a necessity.
Corneal inlays, corneal on-lays and single vision and bifocal contact lenses are also used to correct the vision of the patient. In many cases, these are utilized to correct for the patient's distance and near vision needs. Each of these lenses is a very thin optic and requires curvature when applied on or in the eye.
Presently, all known electro-active elements within an electro-active lens are made of rigid materials. Although an electro-active element may be housed within a flexible outer host material, the electro-active element is rigid and therefore may add some rigidity to the contact lens.